squiggly trees in latex

Question

I need to draws trees, in which one of the branches is squiggly, as showed in the screenshots below. Does anybody know how I can do that?

adapted from: Svenonius, P. (2015). Spanning. Ms., University of Tromso.

adapted from: Merchant, J. (2015). How Much Context Is Enough? Two Cases of Span-Conditioned Stem Allomorphy. Linguistic Inquiry, 46(2).

Thank you in advance!

Answer 1

I would, naturally, use Forest because I happen to like it. It is very powerful and extremely flexible. I would load it with the linguistics library defaults

\usepackage[linguistics]{forest}

use a TikZ library for the wiggly line

\usetikzlibrary{decorations.pathmorphing}

and define a couple of styles for convenience.

\forestset{%
  /tikz/squiggly/.style={decorate, decoration={snake, amplitude=.5mm, segment length=2mm}},

A TikZ style for wiggly lines.

  wiggly/.style={edge=squiggly},

A Forest style for wiggly edges.

  move me/.style n args=2{%
    before drawing tree={%
      x+=#1,
      y+=#2,
    },
  },

A Forest style for moving nodes to strange positions, overriding the locations calculated by the packing mechanism.

}

no edge can be used to block an edge and phantom can be used to create invisible nodes which just help with positioning.

Then the first tree can be drawn with

\begin{forest}
  [root
    [un, no edge]
    [dau, wiggly, no edge, move me={-5pt}{-20pt}]
    [tri, wiggly, move me={-10pt}{-40pt}]
    [pedwar, wiggly, move me={-15pt}{-60pt}]
    [, phantom, calign with current]
    [pump
      [chwech, roof]
    ]
  ]
\end{forest}

Substituting the actual content

\begin{forest}
  [D\textsubscript{[+DEF,+F,-PL]}
  [\emph{un} <D\textsubscript{[-DEF,-F,-PL]}>, no edge, move me={200pt}{0pt}]
  [\emph{une} <D\textsubscript{[-DEF,+F,-PL]}>, wiggly, no edge, move me={100pt}{-20pt}]
  [\emph{le} <D\textsubscript{[+DEF,-PL]}>, wiggly, move me={60pt}{-40pt}]
  [\emph{la} <D\textsubscript{[+DEF,+F,-PL]}>, wiggly, move me={15pt}{-60pt}]
    [, phantom, calign with current]
    [NP
      [école, roof]
    ]
  ]
\end{forest}

produces

The second diagram is not a tree, but it is a tree except for one edge, so I'd just use tikz to add the extra line.

          [I, tikz+={\draw [squiggly] (.parent anchor) -- (!sL.child anchor); }

To get the final nodes aligned, I would use tier and, since there's a regularity here, I'd add wiggly for all terminal nodes and use a phantom to prevent the single exception being aligned at the bottom of the tree.

Then

\begin{forest}
  where n children=0{
    wiggly,
    tier=terminus
  }{},
  [A
    [B
      [D
        [F
          [H
            [J
              [,phantom]
              [K]
            ]
          ]
          [I, tikz+={\draw [squiggly] (.parent anchor) -- (!sL.child anchor); }
            [,phantom]
          ]
        ]
        [G
          [L]
        ]
      ]
      [E
        [M]
      ]
    ]
    [C
      [N]
    ]
  ]
\end{forest}

will produce the second non-tree.

Shamelessly plugging Alan Munn's content into the second structure above,

\begin{forest}
  where n children=0{
    wiggly,
    tier=terminus
  }{},
  [T
    [Asp
      [Voice
        [$v$
          [V
            [$\sqrt{\text{EAT}}$
              [,phantom]
              [fayo]
            ]
          ]
          [$v$, tikz+={\draw [squiggly] (.parent anchor) -- (!sL.child anchor); }
            [,phantom]
          ]
        ]
        [Voice\\\textminus act
          [o]
        ]
      ]
      [Aspect\\+perf
        [ik]
      ]
    ]
    [{T\\+past,1sg}
      [a]
    ]
  ]
\end{forest}

produces

Complete code:

\documentclass[border=10pt,multi,tikz]{standalone}
\usepackage[linguistics]{forest}
\usetikzlibrary{decorations.pathmorphing}
\usepackage{amsmath,textcomp}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\begin{document}
\forestset{%
  /tikz/squiggly/.style={decorate, decoration={snake, amplitude=.5mm, segment length=2mm}},
  wiggly/.style={edge=squiggly},
  move me/.style n args=2{%
    before drawing tree={%
      x+=#1,
      y+=#2,
    },
  },
}
\begin{forest}
  [root
    [un, no edge]
    [dau, wiggly, no edge, move me={-5pt}{-20pt}]
    [tri, wiggly, move me={-10pt}{-40pt}]
    [pedwar, wiggly, move me={-15pt}{-60pt}]
    [, phantom, calign with current]
    [pump
      [chwech, roof]
    ]
  ]
\end{forest}
\begin{forest}
  [D\textsubscript{[+DEF,+F,-PL]}
  [\emph{un} <D\textsubscript{[-DEF,-F,-PL]}>, no edge, move me={200pt}{0pt}]
  [\emph{une} <D\textsubscript{[-DEF,+F,-PL]}>, wiggly, no edge, move me={100pt}{-20pt}]
  [\emph{le} <D\textsubscript{[+DEF,-PL]}>, wiggly, move me={60pt}{-40pt}]
  [\emph{la} <D\textsubscript{[+DEF,+F,-PL]}>, wiggly, move me={15pt}{-60pt}]
    [, phantom, calign with current]
    [NP
      [école, roof]
    ]
  ]
\end{forest}
\begin{forest}
  where n children=0{
    wiggly,
    tier=terminus
  }{},
  [A
    [B
      [D
        [F
          [H
            [J
              [,phantom]
              [K]
            ]
          ]
          [I, tikz+={\draw [squiggly] (.parent anchor) -- (!sL.child anchor); }
            [,phantom]
          ]
        ]
        [G
          [L]
        ]
      ]
      [E
        [M]
      ]
    ]
    [C
      [N]
    ]
  ]
\end{forest}    
\begin{forest}
  where n children=0{
    wiggly,
    tier=terminus
  }{align=center},
  [T
    [Asp
      [Voice
        [$v$
          [V
            [$\sqrt{\text{EAT}}$
              [,phantom]
              [fayo]
            ]
          ]
          [$v$, tikz+={\draw [squiggly] (.parent anchor) -- (!sL.child anchor); }
            [,phantom]
          ]
        ]
        [Voice\\\textminus act
          [o]
        ]
      ]
      [Aspect\\+perf
        [ik]
      ]
    ]
    [{T\\+past,1sg}
      [a]
    ]
  ]
\end{forest}
\end{document}

Answer 2

The first tree is barely a tree, and so you may want to draw it manually with a matrix of nodes. The second tree is fairly straightforward but needs some trickery to have the multidominance structure for the v structure since (as cfr correctly notes), multidominance 'trees' are not strictly speaking, trees.

\documentclass{article}
\usepackage{fontspec}
\setmainfont{Linux Libertine O}
\usepackage{amsmath}

\usepackage[linguistics]{forest}
\usetikzlibrary{snakes}
\tikzset{decoration={snake, amplitude=.4mm,segment length=2mm}}

\begin{document}

\begin{forest} where n children=0{tier=word, edge=decorate}{}
[T [Asp [Voice 
      [v [V\\$\sqrt{\text{\scshape eat}}$,name=V [\phantom{v},no edge]]
      [faɣo,no edge, name=Vroot] 
      [v,name=v [\phantom{v},no edge]]][Voice\\$-$act [θ]]]
   [Aspect\\$+$perf [ik]]] 
   [T\\{$+$past,1sg} [a]]]
\draw[decorate] (v.south) -- (Vroot.north);
\draw[decorate] (V.south) -- (Vroot.north);
\end{forest}

\end{document}